The present invention relates to a coupling for rapidly and detachably connecting a conduit pipe or hose to an opening, provided with an inner sleeve having a flange on at least one end, an outer sleeve capable of moving with little play about the inner sleeve, a groove for a flexible sealing member between the coupling and the opening to be connected, as well as clamping means for the relative axial movement of inner and outer sleeve and for pressing the sealing member tightly into the opening.
In known types of such couplings, a rubber ring is fitted between a flange on the inner sleeve and a flange on the outer sleeve, in such a way that, upon the inner sleeve being moved relatively toward the outer sleeve, the rubber ring is subjected to axial pressure, causing it to be thrust out radially through elastic deformation.
Such a coupling has been found not to ensure a satisfactory seal in all conditions, and specifically not to be resistant to high axial forces.